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Markowitz’s portfolio selection theory was applied in overseas petroleum venture capital investment, the mean of each project’s AT cash was used as the portfolio’s return, the fluctuate rate return of project was used to reflect portfolio’s risk, the combination of minimum risk portfolio optimization decision model was established. A variety of risk definition method were explored, efficient frontier under variety of risk-defined were developed, according to different risk preferences, the investment decision-makers can choose optimal portfolio to maximize investment, so as to reduce and avoid undue loss.

Field study was conducted to determine the optimum irrigation quantity and times of corn in 2010. Different irrigation treatments were set according to local farmers’ practices. Irrigation amounts of T1, T2, T3, T4, T5 and T6 were 225, 270, 337.5, 300, 360 and 450 mm, respectively. Irrigation times of T1, T2 and T3 were 3, and T4, T5 and T6 were 4. The results showed that soil salt decreased with the increasing of irrigation water amounts. The corn yield varied from 6560 to 8060 kg/ha2. The highest yield was obtained from T5. Aiming to get high corn yield, total water supply of corn crops was 865 mm. Irrigation water productivity (Wpi) was the highest (2.92 kg/m3) with T1, and the lowest (1.74 kg/m3) with T6.

Understanding relationships between vegetation and its substrate environment is helpful for protection of ecosystem integrity. Substrate has been proved as one of good indicators to reveal the inherent interactions between wetland vegetation and its environment. A study was thus conducted to investigate the suitable soil environment for salt cedar (Tamarix chinensis) in order to predict its distribution in the Yellow River Delta in whichTamarix chinensishas been spreading in recent years. This study analyzed the soil parameters as environmental variations, and at the same time used proline content as a physiological indicator to illuminate the condition of theTamarix chinensis. The habitats were classified into 3 clusters at 95% confident level with K-mean clustering algorithm. The differences in soil conductivity, Cl-, NO3-, Na+and Mg2+among the three clusters were significant as revealed by ANOVA results. The distribution of these clusters and their soil variations were consistent, implying that the clustering illuminates the differences physically. Finally, a range ofTamarix chinensisleaf proline was settled and compared with the clustering results, and it was found thatTamarix chinensiscould have positive growth dynamic under moderate soil water and salinity conditions.

The saltwater intrusion in the Yangtze River Estuary is very frequent and complicated with a great effect on freshwater supply in Shanghai and nearby cities. By using the hydrologic data observed in dry season, the temporal and spatial variation of the saltwater intrusion in the Yangtze River Estuary were analyzed. The results show that the saltwater intrusion of the south branch is mainly induced by the saltwater spilling over from the north branch, which causes the Chenhang reservoir being plagued by saltwater intrusion during dry season. As the saltwater group from the north branch moving downward along the south branch, the longitudinal salinity distribution present a high-low-high shape during spring tide cycle, low-high-low-high shape during medium tide cycle and low-high shape during neap tide cycle along the south branch-south channel-south passage. Moreover, the north branch is controlled by high saline water with the increase of the salinity in the upstream reach in medium and spring tides, but this phenomenon is vanished in neap tide. In addition, the vertical distribution of salinity is more homogeneous in shoals than that in deep channels, which is induced by mixing degree in water column.

Datong hydrological station is the last control station in the Changjiang River mainstream, and its runoffs have great significance on evolution of the tideway and the estuary of the Changjiang River. Therefore, this paper compiled long term series (1950~2010) of daily water discharges at Datong gauging station, and utilized the statistic methods to analyze the long term evolution characteristics of the Datong runoff. The results show that: (1) Inter-annual variability of runoffs was relatively stable, with average fluctuation range below 104m3/s, which may be caused by the location of the river basin and regulation of many large scale lakes; (2) The monthly runoffs have distinctly seasonal variation characteristics, wherein, the runoffs from June to September occupy 51% within a year, and the other months occupy the residual 49%, moreover, the runoff proportion of flood season within 2003~2010 has a slight decline of 2%, compared with that of 1995~2002.

Biosorption of Cr6 + ions by industrial fermentation waste Aspergillus niger free dry mycelium was investigated in a batch system..The influences of Cr6 +concentration, biosorbent dose, solution pH and contact time on Cr6 +were investigated.Optimum biosorption was observed to be 73.5% at pH 5,biosorbent dose 20g/L, initial Cr6 + concentration 100 mg/L. Adsorption equilibrium was established in 800 min at 30°C. The Langmuir model compared to the Biosorption equilibrium data were best described by Langmuir isotherm model, R2=0.9999.

Based on Solidworks software, the three-dimensional model of two wheels scooter is set up. The finite element model of two wheels scooter is generated. Modal analysis of driving system and telescopic mechanism of bar on two wheels scooter is investigated. The first five orders natural frequency and major modes of driving system and telescopic mechanism of bar are clarified. The method and the result can be used as a reference of dynamic design and lay foundation for calculation and analysis of dynamic response for the two wheels scooter.

In this paper, we present a new approach to improve extracting accuracy of impervious surfaces. One Landsat TM image of Taiyuan city, Shanxi Province of China was used. After doing test work and analyzing using optimum bands analysis, principal component analysis, and normalized difference impervious surface index, we present the method, optimized band combination. Both unsupervised and supervised classification methods were used to classify the original image, principal component analysis image, normalized difference impervious surface index image, and optimized band combination images we present. The accuracies result of these classifications were assessed by using 256 randomly selected sampling points, and it was found that the overall accuracy the accuracy of optimized band combination method can be reach 87.72%, with the Kappa statistic of 0.85 in impervious surface extraction, it was better than other three methods can get.

The structure and function of clothing buttons, to a great extent, influence the clothing modeling, covering function and use function. It is a sign of evolution of clothing. This article elaborates the modern women's clothing buttons type, and the relationship between function and aesthetic culture connotation. The conclusion is button is an important organic part of clothing.

The artifacts design and usage have been evolving since preliminary civilization period from to satisfy pure physical needs gradually to also meet psychological needs. As the evolution result, some artifacts are designed and produced not only with practical or decorative value, but also with purpose to demonstrate the consciousness of rank difference. This article, from social class consciousness perspective, with the analysis on decoration methods, clothing color and materials, demonstrates the explicit and implicit class ideological connotation in Chinese traditional dress. The dress color and pattern are strictly defined for and associated with social classes, where any violation is prohibited. As a conclusion, most artifacts especially Chinese traditional dresses which clearly represent all social classes are the intended product by ruling class.

For the purpose of improving the interference resistance and accuracy of the grating detection system, a SCM-based software design method for grating signal processing is proposed in the thesis. In the method, two differential signals output from the grating detection circuit are amplified and shaped via the conditioning circuit, converted into digital quantity through AD conversion and processed by the SCM. Relying on the programming, properties of direction discrimination and subdivision are attained while effective computation accuracy of subdivided data and signal processing speed are guaranteed. The software processing method simplifies system hardware circuit, cuts down the cost, improves the resolution and measurement precision of the system due to the stable performance and strong interference resistance. The method is experimentally proved to be practical and worthy of promotion, which can be utilized in machine tool reform and relevant position detection systems.

Effluents from potato starch industry possess a high load of starchy materials. The treatment of such wastewater by conventional activated sludge processes consumes a lot of energy, resulting in high treatment costs. A plant growth promoting bacterium (PGPB) Bacillus amyloliquefaciens strain A3 was isolated from soil. The isolate A3 performed a good capacity of promoting tea plant growth, which indicated that the strain can be used as a nonchemical alternative biofertilizer. In this study, we investigated the carbon and nutrient rich industrial processing effluents of potato starch wastewater (PW) as substrate for the cultivation of the biofertilizer strain A3. The isolate A3 can grow well using PW as the culture medium. The maximum yield of 2.2×109 CFU/ml of the isolate A3 was reached in 24 h at 36 °C, pH 7.5 using the SW as substrate. In conclusion, it is feasible to develop a hybrid biotechnological process, integrating the production of environmental friendly biofertilizer with treatment of intractable wastewater.

Through the research on the change of system input and output energy in time-varying speed cutting, the influence of variable-speed waveforms on vibration suppression effect in time-varying speed cutting is quantitatively analyzed in this paper. A conclusion can be drawn that sine wave speed variation is better than triangle wave speed variation in vibration suppression.

Mining, smelting, processing, and industrial production emissions of waste heavy metal pollution is serious, and the enrichment of heavy metals, it is difficult to be degraded in the natural environment. Conventional methods for removing metals may be ineffective extremely expensive. not eco-friendly.Based on wastes recycling and circular economy, this thesis studied the characteristics of industrial fermentation waste A.niger as adsorbent for sequestering Pb(II) from aqueous solution. .Optimum biosorption was observed to be 72％ at pH 5.5,biosorbent dose 1.5 mg／L, initial Pb(II)concentration 250 mg／L.A.niger can be used as a new economic and eco-friendly environmental materials of metal adsorption.

Mesoporous CeO2 was first synthesized by hydrothermal method, and then used to synthesize different content of (Co3O4)x/CeO2 (x was the molar ratio of Cu and Co) by deposition-precipitation method. The fresh and doped catalysts were characterized by X-ray diffraction (XRD), N2 adsorption and desorption, H2 temperature programmed reduction (H2-TPR) and O2 temperature programmed desorption (O2-TPD) to study the crystal structure, surface area, and the mechanism of CO oxidation. The results show that: In XRD pattems, the doped cobalt amounts of samples from x=20% to x=100% have Co3O4 crystal structure. The N2 adsorption and desorption indicated the samples were mesoporous structure. Compared with other samples, the better reducibility and activity oxygen species of (Co3O4)50%/CeO2 coincided with its better catalytic activity.

Edging is Chinese traditional border processing mode. The new symbol meaning and spirit function accumulated in the long development history of the garment trimming culture, have the rich cultural connotation. The edging of women’s common dress is actually used to demonstrate the functional attributes and aesthetic attributes.

Based on field experiment, the yield and water use efficiency (WUE) of tobacco under different nitrogen levels were studied in Hunan province, China. The results show that the evaportranspiration (ET) of flue-cured tobacco dealt with N2 (90kg N fertilizers per ha) gets to the maximum. In addition, the vigorous period has the maximum ET due to the critical period of water requirement. The linear relationship is established among fertilization, yield and water use efficiency. Reasonable fertilizer application can increase water use efficiency and flue-cured tobacco yield.

The blossom-end rot (BER) induced by calcium deficiency will cause a great impact on tomato yield and quality. Aimed at the tomato physical barriers caused by calcium deficiency, the composite micro-organisms (EM) fermentation technology was applied to configure biological active calcium preparations of different calcium concentrations, with raw materials of calcium sulfate, lime and gypsum. The active calcium preparation with calcium concentration of 1 ‰ was sprayed on the fruits during the fruit development period in the field experiment. The results show that lime with highest solubility is the best raw material for the fermentation of EM active calcium preparations with the consideration of higher calcium concentration, reasonable pH and EC value, and the lowest cost. It also shows the incidence of blossom-end rot of the experimental group is 35.36 % lower than that of CK.

This paper introduces the liquid level detecting system, using the laser displacement sensor to realize automatic measurement, using LabVIEW virtual instrument technology to data collection technology, network communication and database management technology are integrated in one system, has simple structure and design, strong universality, expanding the convenience and high efficiency of data transmission. Can be applied to different testing apparatus, the data acquisition system has good universality, is easy to embed other application testing system.

Cylindrocarpon root rot, caused by Cylindrocarpon destructans, is a severe disease on ginseng (Panax ginseng C.A. Meyer) in northeast China. Methyl jasmonate (MeJA) has been studied for its ability to induce plant defenses against pathogens. The effects of MeJA on the colony diameter of C. destructans and seedling growth were examined in vitro. Two-year-old ginseng roots were drenched with MeJA (200 mg/L) and then inoculated with conidia suspension of C. destructans (1×106 conidia/ml). Disease severity was assessed on inoculated roots, and the activation of defense responses was also measured. Results showed that MeJA had no effect on the growth of C. destructans and seedlings at low concentrations. The incidence rate and disease severity on MeJA-treated ginseng roots was significantly reduced compared with untreated roots. The proline content was increased but the malondialdehyde (MDA) content decreased in MeJA- treated roots. The activities of phenylalanine amino-lyase (PAL), catalase (CAT), peroxidase (POD) and polyphenoloxidase (PPO) were significantly enhanced in treated roots. It was concluded that low concentrations of MeJA had no effect on C. destructans, but it stimulated the activities of defense enzymes in treated ginseng roots and alleviated the damage of roots from C. destructans. Therefore, the control of Cylindrocarpon root rot by MeJA may involve the activation of the disease-related defense system.

The spectral degree of polarization is studied based on the cross-spectral density matrix of an elliptically polarized laser beam propagating in the slant path through turbulent atmosphere. In addition, the effects of the turbulence on the spectral degree of polarization of an elliptically polarized Gaussian Schell-model beam and a partially polarized laser beam are contrasted and analyzed. And the different elliptically polarized laser beams are investigated.

Roller is a main tool and consumption parts for steel rolling. With analysis test on the fatigue property of roller, the development incentives of crack propagation were realized, the service life of roller was improved and the cost of Production was reduced in a large extent. Roller is a circular column, which do fixed-axis rotation under combined action of roll pressure, bearing reaction, Support roller reaction force and torsion. The failure types of roll such as flaking, fracture and crack. Simulate and analysis on damage of the roller crack by the fracture mechanics of knowledge and ANSYS, which shown that compressive was large with the ring and axial and compressive was small with the radial direction, so the compressive of radial direction the analysis had little effect on roll surface.

Confronting the problem that echnology parameters are difficult to set in the strip tension levelling process, in this paper takes the tension leveler as research object, using the ANSYS software to make dynamic simulation of strip tension levelling process, mainly analyse relationship between the intermesh and curvature, get result that curvature radius during the straightening process is much larger than bending roller radius, as well as the relationship between curvature and the intermesh under the specific structure condition, the research provides help for the optimization of the tension leveler equipment technology parameters.

For a case of constant-rate liquid production from a single well centered in a horizontal, homogeneous-acting, isopachous, and infinite reservoir, based on fundamentals of fluid flow in porous media the bottom hole flowing pressure never stabilize. In the process of field well testing, however, pressure values measured by the pressure gauge which has a definite resolution value will not change after a period, so the bottom hole flowing pressure can be considered to be stabilized. According to this situation, through theoretical derivation, a stabilized time formula is firstly proposed, by which the time after which the bottom hole flowing pressure measured with a pressure gauge will be stabilized can be calculated, and the stabilized time for a given pressure gauge is in direct proportion to the liquid producing rate, but in inverse proportion to the resolution ratio of the pressure gauge. Applied the stabilized time formula, a new formula of detectable radius can be derived, by which the effect of resolution of the pressure gauge can be considered. Secondly, the time after which the value of the pressure gauge measured in the bottom hole of the observation well starts to change during interference testing is obtained, and the time is related to the fluid flow rate and the distance between the producing well and the observation well. The conclusion can be applied as a reference in the design process of working system during well testing.

In this paper, the triplet properties of a series of 1, 8, 15, 22-tetra-n-pentyloxy metallophthalocyanines [α-MPc(OC5H11)4), M=Fe, Ni, Cu, Zn] and metal free phthalocyanine [H2Pc((OC5H11)4)] were investigated using flash photolysis technique in solutions at the concentration of 10-5mol/L. The triplet absorption curves and triplet lifetimes were acquired. ZnPc(OC5H11)4 exhibits a strong triplet absorption and has long triplet lifetime due to the d-electron and charge transfer effect.

Sulfhydryl lignin was prepared by immobilizing sulfhydryl onto wood lignin. The effect of pH, temperatμre, adsorption time, salinity of condiment and amino acid concentration of condiment on the adsorption behavior of sulfhydryl lignin was investigated, respectively. The adsorption kinetics and thermodynamics of Cu(Ⅱ) were also studied.

Use Design Expert software to establish a quadratic polynomial model between four factors and content of reducing sugar which is characterization for hydrolysis. The four factors are the amount of complex enzyme, the ratio of complex enzyme, hydrolysis temperature and hydrolysis time. Process of sargassum extracts preparation with complex enzyme is optimized by response surface methodology. The optimum preparation conditions were achieved as follows：amount of complex enzyme is 2.05%, ratio of complex enzyme is 1.98, hydrolysis temperature is 55°C, hydrolysis time is 64minutes, and the final reducing sugar content is 0.832% which is good repeatability.

The effects of temperature, time, pH, calcium concentration and the ratio of shelling buckwheat and sodium glutamate were studied while using dipping treatment to accumulate γ-aminobutyric acid (GABA) in north-shaanxi shelled buckwheat. The results were as follows: Glutamate decarboxylase activity is 3.694u/g. The yield of GABA achieves in the largest respectively under the following conditions: Soaking temperature at 40°C, time of 10h, pH6.0, calcium concentration at 0.3mmol/L, the ratio of shelled buckwheat and sodium glutamate at 1800g/mol.

Traditional network management takes network equipment as main management objects, while the network services may failed even if the network devices work well. As a matter of fact, users concern more about the operating states of network services. Considering from users’ perception, this paper proposes a service-oriented network performance management model constructed by the Fuzzy Delphi Analytical Hierarchy Process (FDAHP), which focus on mapping service performance parameters into network performance parameters that can help us deeply understand root faults in communication networks. Simulations and experiments are carried out to prove the validity& correctness of our method.

Raising nitrogen utilization efficiency could not only cut the fertilizer costs, but also reduce the N loss and residual, which benefits a lot to agricultural production and environmental protection. In this experiment, the 15N tracing technique was employed in order to clear the accumulation and whereabouts of fertilizer N in flue-cured tobacco plants, besides, the tobaccos were treated by six different water-nitrogen modes, for the sake of finding out the best design with the highest nitrogen utilization efficiency. The results showed that more N application contributed to more fertilizer N accumulation, also increased the content of total N; Excess irrigation restrained the tobacco plants' absorption of fertilizer N, ultimately leading to the low utilization efficiency of nitrogen fertilizer; After apex pruning, the N offering ability of the soil was much stronger than that of nitrogen fertilizer, and the fertilizer N accounts a relatively small part for the total N in tobacco plants, the highest nitrogen utilization efficiency was 24.16%, recorded in the design of 800mm irrigation amount and 6g/plant pure N application(T2), Meanwhile, the agronomic characters and crop yield was observed, tobaccos in T2 design performed better than the average level of field-cultivated tobaccos, the conclusions could be obtained that T2 design was preferable, which achieved the highest nitrogen utilization efficiency when ensured the normal growth and good harvest of flue-cured tobacco.

Mg2-xNdxNi (x=0.1, 0.2, 0.3) alloys, along with Mg2Ni for comparison, were prepared by vacuum induction melting, The influent of content of Nd on the microstructure and hydrogen storage performance were studied, the hydrogenation mechanism of Mg2-xNdxNi alloys was explored. The results showed that: the hydriding-dehydriding kinetics performance of Mg2Ni were improved by adding Nd, but the hydrogen storage capacity of alloys decreased. Mg2Ni, Nd2Ni7, NdMg12, Nd5Mg41 and other minor phases were observed in Mg-Nd-Ni alloys. Mg-Nd-Ni alloys had favorable kinetics performance. Compared with Mg2Ni alloy, the desorption rate and desorption ratio decreased with the increase of the amount of Nd, the hydriding-dehydriding kinetics performance Mg1.9Nd0.1Ni was the best. The hydrogenation mechanism of Mg2-xNdxNi alloy was nucleation and grown up mechanism controlled by diffusion ([-ln(1-ξ)]n=kt), the nucleation and grown up process was decided by the diffusion of hydrogen atom in alloy. Hydrogenation rate increased with the increase of hydrogen pressure and adding Nd, it was because the diffusive rate of hydrogen atom in alloy increased. According to the analysis of kinetics mechanism, methods to improve kinetics performance was put forward by reducing the diffusion path of hydrogen atom in alloy.

Mg1.7 M0.3 Ni (M = Mg, La, Nd and Ce) alloys were prepared by vacuum induction melting under the high purity helium atmosphere. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were utilized to study the phase structures of tested alloys, and their morphologies and hydrogen storage properties were intensively studied by pressure-composition -temperature (PCT) test. It was found that the Mg-M-Ni(M=Mg, La, Nd and Ce)alloys appeared multiphase structures, and as Nd substituting Mg the Mg-Nd-Ni obtained the optimal activation behavior, plateau characteristics, hydrogen cycling reversibility and kinetic properties.

The effect of annealing treatment on the structure, gaseous hydrogen characteristics and electrochemical properties of the La0.67Mg0.33Ni2.5Co0.5alloys was investigated. Alloy structure analyses show that all of the alloys consisted of complex phases such as (La,Mg)2(Ni,Co)7phase, (La,Mg)(Ni,Co)3phase and La(Ni,Co)5phase. The homogenization of composition was improved by annealing treatment. Gaseous hydrogen characteristics were also improved after annealing. The pulverization of the alloy particles was reduced after annealing treatment, which could improve the cycling stability. Electrochemical experiments show that all of the alloy electrodes exhibited good activation characteristics, that annealing treatment improved the maximum discharge capacities of the alloy electrodes from 371.1 mAh/g (as-cast) to 387.7 mAh/g (1173K). The cyclic stability of alloy electrodes was also improved after annealing. However, the high rate dischargeability characteristics were deteriorated.

The thin-walled complex parts reverse engineering is very different from conventional parts or the parts have some simple surface reverse engineering. There are some features. For example, it may have a lot of surface, structure complex, and it is difficulty that scanning point cloud data. Through this thesis, we put a stent by pedal as a thin-walled complex part, introduced some technology about it reverse engineering.

In the tension leveling process, calculation of the strip elongation by the traditional method only considers the extension rate after the tension response, while ignoring elastic bending recovered, so the calculation of elongation is large enough to affect the process control accuracy. This paper considers not only the residual strain after elastic bend recovery, but also the affection of the residual deformation under plain cross-section assumption. The calculation of the elongation is less 4-10% than that of the traditional one. It shows that parameters of the tension leveling process set by the new method will be calculated accurately.

This paper takes a new kind of planar 3-DOF parallel manipulator with actuation redundancy as the object of study. We utilize a design space to obtain the relationship between the link lengths of planar 3-DOF paralel manipulator with actuation redundancy and performance criteria based on the global conditioning index. The corresponding performance atlases has been plotted, the atlases are an important base of reference for the mechanism design of this parallel manipulator.

With Larch timber as the experimental subject, according to the visual grading-related rules in ASTM D245, four-point bending edge-wise in ASTM D4716-05 and axial strength in tension, the regression analysis is conducted; investigate the correlation relationship of Kus, E4s and σw. The result demonstrates that the combination of visual grading, density and four-point bending MOE, the predict of the parallel tensile strength will be more exactly whose correlation coefficient is 0.750.

In this paper, we investigated the structure of SmCo films with different thickness and the effects of Cr buffer layer on the structure and morphology of SmCo/Cu thin films. Our data revealed that the magnetic properties of the samples were enhanced by the crystallization of SmCo which was promoted by the optimized Cu underlayers. We also found that the surface roughness can be decreased by Cr layer and the texture can be improved by prolonging the annealing time for thick SmCo film. Thus, we concluded that the magnetic properties of SmCo/Cu films can be further optimized by varying the thickness of Cr buffer layers.

In order to improve the city environment, and achieve a leap in making reasonable use of natural gas and optimizing energy structure, the Beijing municipal government has established its basic policy to “transform its coal-based energy structure, introduce large amount of natural gas”. As the wall-hung gas boiler has easy operation, flexible adjustment and high energy efficiency, the application of it is becoming more widely considered among the residential building. The work proposes the survey of the heating way about affordable housing and the “two limit” commodity housing in Beijing. The adaptability between the household wall-hung gas boiler heating way and other heating ways is compared. The energy efficiency, initial investment and operating cost of all the heating ways that are being used in Beijing are discussed in the paper. The final analysis is then evaluated by a panel of experts to determine its accuracy and potential for use in a greenway development plan of heating way in Beijing. Analysis shows that the commercial housing is more suitable than affordable housing to use the wall-hung gas boiler. This is mainly be effected by the characteristics of the user’s economic condition and the residences’ distribution.

By analyzing the characteristics of the circulating water control system with constant pressure, we established the mathematical model of the system. However, the system with conventional Proportional-Integral-Differential (PID) controller can not achieve excellent dynamic and static performance. An adaptive Fuzzy-PID controller was designed by combining Fuzzy and PID control methods. And we simulated the system in MATLAB/Simulink with the methods of conventional PID and Fuzzy PID respectively. Compared with the method of conventional PID, the results showed that the method we had proposed has the better effect than conventional PID

The construction of indemnificatory housing has been speeded up from 2009 so as to tackle the difficulty in housing for low-income families in Beijing. With an increasing emphasis on easy operation, flexible adjustment and high energy efficiency, the application of the wall-hung gas boiler are becoming more widely considered among the indemnificatory housing building as a competitive or alternative way to district and central heating. The work proposes the survey of the heating way about indemnificatory housing buildings including low-rent housing, indemnificatory housing and policy-regulated rental housing. The SWOT audit is employed to analyze the satisfaction index of the wall-hung gas boiler and other heating ways. The final analysis is then evaluated by a panel of experts to determine its accuracy and potential for use in a greenway development plan of heating way in Beijing.

Anthocyanins, which possess strong antioxidant activities, are abundant in purple sweet potato wine. In the present study, changes in the antioxidant activity of purple sweet potato wine during storage were investigated. The results showed that purple sweet potato wine had high 2,2-dipheny-l-picrylhydrazyl (DPPH) free-radical and superoxide-radical scavenging activities, which were stable during storage periods. Compared with these two scavenging activities, the hydroxyl-radical scavenging activity of purple sweet potato wine was concentration-dependent and only presented relatively obvious scavenging activity at high concentrations. This hydroxyl-radical scavenging activity was also stabile during storage periods. The results are valuable in purple sweet potato wine research and development.

This study focused on the distribution and pasting properties of starches in sweet potato (Ipomoea batatas L.) tuber. A fresh sweet potato tuber was cut into six equivalent parts. The extractable contents and pasting properties of starches from different parts of fresh sweet potato tuber were determined. The results showed that the extractable content of starches from the Middle section of sweet potato tuber is lower than that from the head and the end section of sweet potato tuber. The extractable content of starches from the inner-end part and the outer-Middle part of sweet potato tuber are 16.2% and 10.3% respectively. The amylose content of starches is relatively higher in the Middle section and outer layer of sweet potato tuber. The amylose content of starches from the outer-Middle part and the inner-end part of sweet potato tuber are 29.5% and 26.7% respectively. Pasting properties of starches from different parts of sweet potato tubers are different from each other. Among them, the starches from inner-end part of sweet potato tuber have the highest viscosities and a lower breakdown.

Purple sweet potato pigment is a natural food pigment, the stability is important to its quality assurance. The effects of metal ions on the stability of purple sweet potato pigment were investigated. The results showed that Mg2+and Fe3+ were conductive to pigments stability in the initial storage, and with the concentration increased, the pigment was more stable. But K+, Ca2+, Na+, Cu2+, Mg2+ and Fe3+ had brought the color density, the color intensity and the preservation rate of purple sweet potato pigment down in the long-term storage.

With an increasing emphasis on easy operation, flexible adjustment and high energy efficiency, the application of the wall-hung gas boiler are becoming more widely considered among the residential building as a competitive or alternative way to district and central heating in Beijing. It meets the implementation of the policies in twelve-five year plan of China: improving Beijing’s environment and future sustainable transform on its coal-based energy structure. A survey of the heating way of indemnificatory housing, price-fixed housing and affordable housing in Beijing is proposed. The results show that the heating area using the wall-hung gas boiler in the resident building is 55% of the total heating area in Beijing and 67% of the total heating area in new buildings. Then, the adaptability between the household wall-hung gas boiler heating way and other heating ways is compared. The energy efficiency, initial investment, operating cost and user satisfaction are discussed. The final analysis is then evaluated by a panel of experts to determine its accuracy and potential for use in a greenway development plan of heating way in Beijing.

Removed at authors request due to error in the methodology.

Removed at authors request due to error in the methodology.

The uncertain and random characteristics of wind energy make the problem of wind turbine control interesting and challenging. This work investigates an adaptive method for variable speed control of wind turbines under varying operation conditions. For fixed-speed operation of wind turbines, maximum power conversion can be achieved only at a particular wind speed, thus variable speed control of wind turbines is of practical interest in enhancing wind turbine operating efficiency over wide wind speeds. Based on the nonlinear dynamic model of wind turbine, adaptive algorithms are developed in accommodating unknown system parameter uncertainties. This method is shown to be able to achieve smooth and effective tracking of rotor angular speed to capture maximum wind energy. The effectiveness and adaptation of the proposed approach is validated via numerical simulation.

In this paper, the performance of concrete is studied through different water-cement ratio, different air-content, different mineral admixtures, different admixture contents, examined the mechanical properties of concrete, electric flux and chloride ion penetration depth of different mix concrete. The results show that, decreasing w/c ratio, proper air content, adding mineral admixtures can improve the resistance of chloride-permeation. Within some contents, the chloride-permeation resistance using silicides is better than that of fly-ash or slag. On this basis, the proper scheme of mix ratio used in saline area is recommended: the air-content is 3%～5%, the content of fly-ash or slag is 20%～30%, the content of silicides is 6%～8%, and double mixed with silicides.

CdO nanoparticles with different sizes were synthesized by a simple thermal decomposition reaction of precursor obtained by room-temperature solid-state grinding reaction between Cd(CH3COO)22H2O and NaOH in the presence of PEG400. Composition, structure and morphology of the products were analyzed and characterized by X-ray diffraction technology, Transmission electron microscopy and Fourier infrared spectra. The formation of CdO nanoparticles is thought that the nucleation rate of the reactive system is far excess the growth rate of particle. Optical properties of the products were recorded, and the results show that Ultraviolet-visible (UV-vis) spectra exhibit distinct blue shift in comparison with them of the bulk CdO, which is because that the quantum confinement effect of the products is larger than the Coulomb effect. Photoluminescence (PL) spectra exhibit green and red emission bands around 520 and 720 nm respectively.